 Joined: 21/01/2004(UTC) Posts: 1,275
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Hi all, I'm currently in the process of designing a layout for my father. The trackplan is already decided on, and now I'm making assembly drawings in AutoCAD to make the base structure. Since my father is not that technically skilled I intend to make IKEA like instructions so that if he follows the plan he will get a perfect layout. This means I need specify all dimensions correctly in the plan. My question now is this, what is the maximum slope I can allow? As a baseline I would like to be able to pull my metal Rheingold coaches over the slope without issues. The layout basically has 2 slopes, where the trains can enter a hidden station. It will be made in C-rail, and consists of 12 pieces of 180mm straight track (actually the 172mm & 188mm mixed but whatever). Say I need 100mm height difference over that distance (12*180mm=2160mm) the slope would be 4.63%. It looks like this in a diagram (purple line), the Y-axis indicates the height difference in mm, the X-axis the distance, also in mm:  The problem is (I think) that I cannot go from a 0% slope to a 4.63% slope. I need to smooth this one out and gradually increase/decrease the slope. For this I calculated the red slope, which is based on the sigmoid function (y = 1/(1-EXP(-x)) ). You can clearly see that the difference in slope is much less, but the maximum slope (around 1080mm) is much worse. Do you have any opinion about what the maximum slope can be and what the maximum slope difference, from trackpiece to trackpiece, is allowed to be? In my example in the diagram the maximum slope in the middle is 7.4% but the maximum difference from track to track is only 2%. If I lower the maximum allowed difference the maximum slope in the middle goes up. Someone clever might say that I should increase the distance or decrease the height, well, I haven't got the space for it  . If you are interested, I can post the openoffice calc sheet here too. Bert
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 Joined: 22/01/2009(UTC) Posts: 14,879 Location: On 1965 Märklin Boulevard just around from Roco Square
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Without any technical data, your intended slope is in my mind unworkable without decreasing the height and increasing the lenght.
Reading your question, I thought you've answered it as well.
There is no magic solution. 2-3 promille is usually the norm for any slope or rise.
What goes up has to come down.
I'm not saying that working out mathematically is not the way to go but than you have to apply certain rules and regulations.,as you obviously doing.
for example you can't build a step a meter high because you've got no room for it to extend it to reach point A to B.
I found this with my layout, mind you I did'nt work on a proper designed plan.
Another option you have, build a mokup slope and see what happens. will the passenger carriages or the loco be able to run freely over the slope and rise.
A lot of times tunnels have been placed too close to the track and carriages scrape along the tunnel entrance wall.
If you go by a protoypical design, you know yourself you cannot achieve this goal. anything else is by trail and error and the endproduct is something you have to be happy with.
If it finishes up like a roller coaster, only you can decide if this acceptable.
regards.,
John
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 Joined: 08/08/2003(UTC) Posts: 1,614 Location: Birmingham,Alabama
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I have found that the slope of 4% is the most that is workable. However that is only part of the problem.
The slope should be smooth and even. Transition points in particular can be troublesome.
Most steamers have a fairly fixed undercarriage and this length is the problem That I encountered. if there are any dips or rises, I found that the steamers will hand up with driving wheel spinning and no movement.
I found using Woodland Scenics Pre Formed 4% Foam Risers works better for me. You have four sections that togethr are eight feet long and work very well.
I am covering the top of the foam risers with thin balsa to provide something to secure the tracks to.
Just my 2 Cents,
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Train Collection Insured by "Croc's" with "Big Boys" as Backup"
CS/MS Digital Era 1/2
Apple Man iPhone / Macbook Pro / iPad - the end of the windows PC occurred on April 4, 2010.
Love those Era 1 Tank Locomotives - the more the merrier.
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Joined: 21/01/2004(UTC) Posts: 1,275
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The design is in no way intended to be prototypical, but more to maximize use of space. I would like to know what, in your opinion, is possible on straight track for an avarage load controlled Marklin locomotive hauling Rheingold coaches.
Part of my 'problem' is caused by the fact that I want to run electrics with their pantos up, without having to add catenary in the tunnels. I might have to rethink this.
Bert
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Joined: 09/02/2009(UTC)
Posts: 983
Location: ,
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Bert One way is to try before building. A length of wood on the floor supported by books to increase the height at one end (thin books will increase the height by small amounts) lay your C track and run the locos you will use with their maximum weight being pulled and see how high you can go before the loco slips.
This I know is to say the least basic but does work.
I agree that the Woodland Scenics ramps are good although a bit expensive.
I presume a helix is not possible.
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davemr |
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Joined: 16/02/2004(UTC)
Posts: 15,466
Location: DE-NW
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Quote:[size=1" face="Verdana" id="quote]quote:Originally posted by DasBert33
<br />The problem is (I think) that I cannot go from a 0% slope to a 4.63% slope. I need to smooth this one out and gradually increase/decrease the slope. I'd add one or two straight tracks for the transition. If you go for 9 mm per 18 cm with one intermediate step, I'd make that 3 mm (first pole: 3 mm, second pole: 9 mm, third pole: 18 mm). If you go for 9 mm per 18 cm with two intermediate step, I'd make that 1.5 mm and 4.5 mm (first pole: 1.5 mm, second pole: 4.5 mm, third pole: 9 mm, fourth pole: 18 mm). I think I'd use short pieces (24077, 24094) in the transition areas to make it even smoother. Up to 7% are prototypical (in Switzerland). In Germany main lines normally don't go above 2% (with some exceptions where they need locomotives that help pushing uphill). One exception is the ICE relation between Cologne and Frankfort (but this was built for ICE 3 and currently only ICE 3 is running there). And M*'s ICE 3 is a bad climber with only 2 powered axles (prototype: 16 powered axles). If you can keep the slope below 4%: good. Below 3%: even better. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS  |
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Joined: 19/12/2008(UTC)
Posts: 207
Location: Durango, Colorado
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For the start of the slope, the transition from level to uphill, I find wood shims work very well. Just cut off the length you want. Woodland Scenics has incline starters which I imagine would do well for the transition - I will be trying them on a layout I will be constructing soon.
Dan
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Joined: 13/11/2008(UTC)
Posts: 381
Location: Richmond, Virginia
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I admit to struggling with a similar problem. I've put everything together in a sloppy pre-build of the layout using books, old boards, and even cardboard: http://smg.photobucket.c...amp;current=MOV00001.flvIt seems to work; but, the tight curve of the "up and over" out of the yard seems to be ugly. I will extend the middle of the curve to extend the slope as in: http://img.photobucket.c...r_stage_larger_table.jpgI used blocks that get me from 1cm to 10cm at the highest point over the yard. I chose 10cm because I want to add catenary like Bert. Using the "back straight" to extend the ramp seemed to work well. Using the shorter 24077 pieces seems an excelent idea for smoothing the transition. Ralph
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 Joined: 17/09/2006(UTC) Posts: 18,778 Location: New Zealand
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Bert, as others have suggested, the transition points are most important. Steam locos in particular can have issues if the transition point is too sharp - they go light on the front bogie and will derail. There is also a good possibility coaches will uncouple. Try to keep the transition points on a straight bit of track if you can to minimise all of this.
Check the Marklin catalogs in the bridge section. There are recommendations there for pillar heights. Also in hidden area you could use threaded rods for your risers. That way you could make adjustments easily if needed.
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 Joined: 16/08/2006(UTC) Posts: 5,382 Location: Akershus, Norway
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Interesting topic, Bert!
I have an additional question to the experiemced layout constructors out there:
Is it and difference if the hill is straight or if it is in a curve?
The reason for my question:
All Märklin locomotives have fixed axels between the left hand side and the right hand side wheels.
When driving in curves, the outer rail is longer than the inner rail. As the LH and RH wheels are turning with the same speed, there must be some wheel slip, either on the inner or the outer wheel.
This reduces the traction.
Does this have any practical influence on the pulling power? |
Best regards Svein, Norway
grumpy old sod
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 Joined: 23/08/2004(UTC) Posts: 764 Location: Bury St. Edmunds, Suffolk
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Hi,
Your plan for a gradient needs simple track planning rather than maths. If you want to run a heavy train such as the Reingold with 5 coaches you will need a very gentle slope more like 3 degrees, it also varies with which engine you use as their pulling power is variable. The only way to test is to build an experimental slope of varying heights and see what suits your setup. ie the slope will need about 12 pieces of track. On my analoge M track layout my slope is closer to 4 degrees and my da 800 loco just manages a 3 coach load. I dare say it is different with c track but with m track having curves in the slope needs extra careful track alignment to a avoid derailments and limits the speed if you need to "rush" the slope
regards
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Regards
Geoff (UK)
marklin HO from the 50's and 60's |
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Joined: 10/02/2006(UTC) Posts: 3,997
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Joined: 19/12/2008(UTC)
Posts: 207
Location: Durango, Colorado
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Bert, regarding curvature on ascents/descents, I needed to bank the curves to avoid truck derailment with my GG1: https://www.marklin-user...ult.aspx?g=posts&t=10574"A little bit of curve banking solved a problem I had with the GG1 on ascending/descending curves (~4% slope). I first noticed that on ascending a curved track section (R2), the GG1's front wheels of the front truck jumped the rails. On a descent, this also occured and sometimes the front wheels of the rear truck also jumped. The jumps did not occur at a track junction but partway along the track. This didn't happen with other locos (steamers - BR86 and BR50). I also had no problems with the GG1 on unbanked level R1 and R2 curves." Dan
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Joined: 22/01/2009(UTC) Posts: 14,879 Location: On 1965 Märklin Boulevard just around from Roco Square
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Quote:Originally posted by DasBert33<br />Hi all, I'm currently in the process of designing a layout for my father. The trackplan is already decided on, and now I'm making assembly drawings in AutoCAD to make the base structure. Since my father is not that technically skilled I intend to make IKEA like instructions so that if he follows the plan he will get a perfect layout. This means I need specify all dimensions correctly in the plan. Here is a photo from my layout representing a bridge and both sides of the track are curved and descending.    The best way is to build it try it and alter it if needed. this particular trackline is a branch line and has'nt got 303mm carriages and it would'nt be suited for that. |
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Joined: 16/02/2004(UTC)
Posts: 15,466
Location: DE-NW
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Quote:[size=1" face="Verdana" id="quote]quote:Originally posted by intruder
<br />Does this have any practical influence on the pulling power?
Yes, locos w/o load regualation slow down in curves. In curves the tractive power of the loco is weaker. Go for wide radii if you can't avoid curved slopes. On double tracks, use the outer track for uphill. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS |
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Joined: 16/02/2004(UTC)
Posts: 15,466
Location: DE-NW
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Hi, Geoff! Quote:[size=1" face="Verdana" id="quote]quote:Originally posted by drstapes
<br />On my analoge M track layout my slope is closer to 4 degrees and my da 800 loco just manages a 3 coach load. I left school some decades ago but IIRC 4° are almost 7%. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS |
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Joined: 23/08/2004(UTC) Posts: 764 Location: Bury St. Edmunds, Suffolk
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Tom,
" left school some decades ago but IIRC 4° are almost 7%"
Well I don't know what that means.. but I dare say you are right. The point of the matter is the gentler the slope the less potential trouble you are goung to have.Also building an experimental slope to test out your ideas is really a good thing to do.
regards
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Regards
Geoff (UK)
marklin HO from the 50's and 60's |
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Joined: 16/02/2004(UTC)
Posts: 15,466
Location: DE-NW
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Geoff,
there are different ways to measure slopes.
And 4° are steeper than a person used to percent measurement expects at first glance. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS |
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Joined: 09/01/2007(UTC)
Posts: 589
Location: The Netherlands
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Quote:[size=1" face="Verdana" id="quote]quote:Originally posted by drstapes
<br />Tom,
" left school some decades ago but IIRC 4° are almost 7%"
Well I don't know what that means.. but I dare say you are right. The point of the matter is the gentler the slope the less potential trouble you are goung to have.Also building an experimental slope to test out your ideas is really a good thing to do.
regards
It means - I guess - that if he remembers right, a 4 degrees slope is 7 cm on a meter. That is correct, and that is very steep.  I've got a grade of 10 cm in 2.5 m which most M* locs can manage even with a heavy train (e.g. a BR18 Rheingold with 5 coaches, which is not a good puller, or a BR96 with a heavy 2.5 m. train). On the other hand, an Electrotren NS 1300 does not manage this, in spite of its many powerede axles. Something inside goes wrong then (plastic gears ??). So I guess 4% is about the max., 5% when running only light trains. The M* bridge elements only do about 2% (4 mm per element). I think the suggestion to use short track element in the beginning and in the end of the slope is very good. For best pulling results it's best not to have different angles in every piece of track since every change of angle will result in a spot of bad pulling! Rgards, Henk |
C and M track; CS1R and 2 MS |
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Joined: 23/08/2004(UTC) Posts: 764 Location: Bury St. Edmunds, Suffolk
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Thanks Guys for explaining what I really meant <g>!
regards
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Regards
Geoff (UK)
marklin HO from the 50's and 60's |
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Joined: 23/08/2004(UTC)
Posts: 73
Location: Helsinki,
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Such a steep slope is far beyond all recommendations, but I had 5-6 % gradient in R2 curve (437.5 mm), and I had no problems with large locomotives with good and clean traction tyres and 4 coaches or about 10 freight wagons. If your 7 % slope is on straight track, it probably works with some train length limitations. But even if it worked for me, I do not recommend that kind of potential problem source. You should make a temporary test slope with simple cardboard structure and test those trains which you want to use before you make a real layout.
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 Joined: 14/03/2005(UTC) Posts: 15,871 Location: Gibraltar, Europe
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Real railways go to great lengths to avoid slopes, which is why you get so many enbankments, cuttings, tunnels and bridges. After many experiments with grades on the living room floor, I can see why they do!
I remember a magazine article I read once which dealt with this problem, and it advised you to keep the track flat, but make the scenery go up and down instead, giving the impression of vertical movement without all the problems. If what you want is hidden sidings (shadow station), you can have a range of hills along the back of your layout with the sidings underneath. In my ultimate layout I plan to have a solution like this.
If you must have changes in altitude, you can try to use the whole length of the layout to slowly climb to the next level, with only the station area perfectly flat. In my opinion, steep slopes are about as prototypical as R1 curves, and much more problematical. |
Ray
Mostly Marklin.Selection of different eras and European railways
Small C track layout, control by MS2, 100+ trains but run 4-5 at a time.
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